Font Management...

I have been using OS X and macs for Years but still feel like a noob in many ways. I use CS3 and Office and FCP Studio etc doing graphics and webdesign and video and such. I have never until now started trying to manage Fonts. Way to many fonts I have searched font management on here and done some reading. I presently have Linotype Font Explorer and use Font book too. SO, on to my questions..

1. Can I make it so each program can use certain fonts?

I dont need Word to have 500 fonts just the ones I use there - Maybe 20.
Same with FCP and Photoshop - they have different uses for me..

2. I just read somewhere about replacing the system fonts with Truetype? Whats the difference?

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